Armstrong County, Pennsylvania
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Armstrong County, Pennsylvania.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Gilpin-Weikert channery silt loams, 25 to 70 percent slopes | 112K | Well drained | C | Very limited | Very limited |
| Gilpin-Weikert channery silt loams, 15 to 25 percent slopes | 39K | Well drained | C | Very limited | Very limited |
| Ernest silt loam, 8 to 15 percent slopes | 30K | Moderately well drained | C/D | Very limited | Very limited |
| Ernest silt loam, 3 to 8 percent slopes | 18K | Moderately well drained | C/D | Very limited | Very limited |
| Rayne-Gilpin channery silt loams, 8 to 15 percent slopes | 16K | Well drained | C | Very limited | Very limited |
| Wharton silt loam, 3 to 8 percent slopes | 13K | Moderately well drained | C/D | Very limited | Very limited |
| Bethesda very channery silt loam, 8 to 25 percent slopes | 12K | Well drained | D | Very limited | Very limited |
| Gilpin channery silt loam, 3 to 8 percent slopes | 12K | Well drained | C | Very limited | Very limited |
| Wharton-Gilpin silt loams, 15 to 25 percent slopes | 10K | Moderately well drained | C | Very limited | Very limited |
| Bethesda very channery silt loam, 25 to 75 percent slopes, very stony | 9K | Well drained | D | Very limited | Very limited |
| Cavode silt loam, 3 to 8 percent slopes | 9K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Water | 8K | Not rated | Not rated | ||
| Bethesda very channery silt loam, 8 to 25 percent slopes, very stony | 8K | Well drained | D | Very limited | Very limited |
| Rayne-Gilpin channery silt loams, 3 to 8 percent slopes | 8K | Well drained | C | Very limited | Very limited |
| Gilpin-Weikert channery silt loams, 8 to 15 percent slopes | 7K | Well drained | C | Very limited | Very limited |
| Wharton-Gilpin silt loams, 8 to 15 percent slopes | 7K | Moderately well drained | C | Very limited | Very limited |
| Cavode silt loam, 8 to 15 percent slopes | 7K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Gilpin-Weikert channery silt loams, 3 to 8 percent slopes | 7K | Well drained | C | Very limited | Very limited |
| Wharton silt loam, 8 to 15 percent slopes | 7K | Moderately well drained | C/D | Very limited | Very limited |
| Ernest silt loam, 15 to 25 percent slopes | 6K | Moderately well drained | C/D | Very limited | Very limited |
What This Means
Building & Foundations
About 97% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas. A geotechnical assessment is recommended before building.
Septic Systems
About 97% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.